* {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
}

html, body {
  width: 100%;
  height: 100%;
  background: url(../images/index_bg.png) no-repeat;
  background-size: 100% 100%;
}

.box {
  width: 100%;
  height: 100%;
  display: flex;
}

.box .left-box {
  width: 25%;
  height: 100%;
  background-color: beige;
}

.box .content-box {
  width: 50%;
  height: 100%;
  background-color: blueviolet;
}

.box .right-box {
  width: 25%;
  height: 100%;
  background-color: brown;
}
